Inkjet printhead that incorporates feed back sense lines
View Patent ↗An inkjet printhead includes an ink distribution assembly for connection to an ink supply and defines a plurality of ink outlets. An array of printhead chips is positioned on the ink distribution assembly. Each printhead chip includes a substrate that defines a plurality of ink supply passages in fluid communication with respective ink outlets. An array of nozzle arrangements is positioned on the substrate. Each nozzle arrangement defines a nozzle chamber connected to an ink supply passage and a nozzle connected to the nozzle chamber. A plurality of actuators is displaceable relative to the substrate to eject ink from respective nozzles. A plurality of feed back sense lines is connected to each printhead chip for providing a controller with data representing operating characteristics of each printhead chip.
1. An inkjet printhead which comprises:
an ink distribution assembly for connection to an ink supply and defining a plurality of ink outlets;
an array of printhead chips positioned on the ink distribution assembly, each printhead chip comprising:
a substrate that defines a plurality of ink supply passages in fluid communication with respective ink outlets;
an array of nozzle arrangements positioned on the substrate, each nozzle arrangement defining a nozzle chamber connected to an ink supply passage and a nozzle connected to the nozzle chamber; and
a plurality of actuators displaceable relative to the substrate to eject ink from respective nozzles; and
a plurality of feed back sense lines connected to each printhead chip for providing a controller with data representing operating characteristics of each printhead chip including temperature of the printhead chip, voltage available to each actuator, resistivity of a heater of each actuator, and a formed width of the heater of each actuator, the controller being configured to adjust timings of nozzle firing pulses in response to the fedback temperatures and to adjust pulse widths of the nozzle firing pulses in response to the fedback voltages, resitivities and widths.
2. An inkjet printhead as claimed in claim 1 , in which the ink distribution assembly includes an ink storage arrangement connectable to the ink supply and a manifold positioned on the ink storage arrangement to receive ink from the ink storage arrangement, the manifold defining the plurality of ink outlets.
3. An inkjet printhead as claimed in claim 2 , in which the ink storage arrangement is elongate, spans a print area and defines a number of longitudinally extending ink chambers.
4. An inkjet printhead as claimed in claim 3 , in which the manifold defines a number of series of slots, each series in fluid communication with a respective ink chamber, the slots defining inwardly converging ink flow paths that open at the ink outlets.
5. An inkjet printhead as claimed in claim 2 , in which the manifold defines an elongate recess into which the ink outlets open and in which each printhead chip is mounted.
6. An inkjet printhead as claimed in claim 1 , in which a plurality of control logic and associated power transistor circuits are positioned on the substrate, each actuator being elongate and fast at one end to the substrate to be connected to a respective control logic and associated power transistor circuit to receive electrical signals from the circuit and to be displaced relative to the substrate on receipt of such signals.
7. An inkjet printhead as claimed in claim 6 , in which a plurality of ink ejection members are positioned in respective nozzle chambers and connected to opposite ends of respective actuators such that displacement of the actuators results in the ejection of ink from respective ink ejection ports.
8. An inkjet printhead as claimed in claim 1 , in which at least one temperature sensor is attached to each printhead chip, the, or each temperature sensor being connected to one of the feed back sense lines.